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Hedging Activities - Narrative (Details) € in Millions, $ in Millions | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Jun. 30, 2026 USD ($) | Jun. 30, 2025 USD ($) | Jul. 31, 2026 CAD ($) | Jul. 31, 2026 EUR (€) | Jun. 30, 2026 CAD ($) | Jun. 30, 2026 EUR (€) | Mar. 31, 2026 CAD ($) | Mar. 31, 2026 EUR (€)
Derivative [Line Items] |  |  |  |  |  |  |  |
Gains (losses) related to cash flow hedges | $ 0 | $ 0 |  |  |  |  |  |
Floating interest rate swaps | Cash Flow Hedges | Derivatives designated for hedge accounting |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |
Notional amount, entered into during period |  | $ 550,000,000 |  |  |  |  |  |
Currency swap | Net Investment Hedging | Derivatives designated for hedge accounting | CAD |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |
Notional amounts of derivative |  |  |  |  | $ 6,500 |  | $ 6,500 |
Currency swap | Net Investment Hedging | Derivatives designated for hedge accounting | CAD | Subsequent Event |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |
Derivative, notional mount, terminated |  |  | $ 6,500 |  |  |  |  |
Notional amounts of derivative |  |  | $ 7,500 |  |  |  |  |
Currency swap | Fair Value Hedges | Derivatives designated for hedge accounting | EUR |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |
Notional amounts of derivative | € |  |  |  |  |  | € 500 |  | € 500
Currency swap | Fair Value Hedges | Derivatives designated for hedge accounting | EUR | Subsequent Event |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |
Notional amounts of derivative | € |  |  |  | € 500 |  |  |  |
Currency swap | Cash Flow Hedges | Derivatives designated for hedge accounting |  |  |  |  |  |  |  |
Derivative [Line Items] |  |  |  |  |  |  |  |
Gains (losses) related to cash flow hedges | $ 7,000,000 |  |  |  |  |  |  |

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